This application relates generally to radar. More specifically, this application relates to methods and systems for retrieving parameters in networked radar environments.
One of the fundamental objectives of meteorological radar systems is to sample the atmosphere surrounding the Earth to provide a quantitative measure of precipitation. Conventional meteorological radars provide coverage over long ranges, often on the order of hundreds of kilometers. A general schematic of how such conventional radar systems function is provided in FIG. 1. In this illustration, a radar is disposed at the peak of a raised geographical feature such as a hill or mountain 104. The radar generates an electromagnetic beam 108 that disperses approximately linearly with distance, with the drawing showing how the width of the beam 108 thus increases with distance from the radar. Various examples of weather patterns 116 that might exist and which the system 100 attempts to sample are shown in different positions above the surface 112 of the Earth.
In these types of arrangements, the radar tends to be relatively large. This is a consequence of the geometry and physics of the configuration being studied. In particular, it is desirable to have the radar beam 108 propagate over large distances without attenuation, as might result from interaction of the beam 108 with precipitation in the system. Such conventional systems thus often use S-band radars, whose operational frequencies of 2-4 GHz have minimal attenuation when passing through precipitation. Such frequencies correspond to wavelengths of about 8-15 cm. The wavelength generated by the radar is approximately related to the size of the radar, with S-band radars thus being relatively large. Indeed, it is not uncommon for S-band radars to have dishes that exceed 25 feet in diameter. In addition, as the drawing in FIG. 1 illustrates, a tendency with conventional radar arrangements is to sample portions of the atmosphere that are further above the surface 112 of the Earth at greater distances from the radar; this is a natural result of the geometry imposed on the system by the curvature of the Earth.
It would be desirable to have a system that uses radars at shorter wavelengths since this would permit generally smaller dishes to be used. For example, C-band radars operate at frequencies of 4-8 GHz, which corresponds to wavelengths of 4-8 cm; X-band radars operate with frequencies of 8-12 GHz, which corresponds to wavelengths of 2.5-4 cm; and K-band radars operate with frequencies of 12-40 GHz (with a gap in the band between 18 and 27 GHz due to a strong absorption line in water), which corresponds to wavelengths of 0.75-2.5 cm (with a gap between 1.2 and 1.7 cm). Simple replacement of radars with higher-frequency radars is precluded without some mechanism for accounting for the increase in attenuation that results at higher frequency.
There is accordingly a general need in the art for improved methods and systems for operating radar arrangements.